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Optimized derivatization of primary amines with the fluorogenic reagent naphthalene-2,3-dicarboxaldehyde toward reproducible quantitative analysis in biological systems
No full textPrimary amines are the target of many bioanalytical analyses, as they are ubiquitous in biological systems and responsible for numerous important processes including neurotransmission and cell signaling. Primary amines can be sensitively detected via fluorescence after their reaction with the fluorogenic reagent naphthalene-2,3-dicarboxaldehyde (NDA) in the presence of cyanide through the formation of fluorescent N-substituted 1-cyanobenz[f]isoindole (CBI) derivatives. While fluorogenic reagents such as NDA can be advantageous for sensitive detection, improvements in both long-term stability and speed of reaction are necessary to enable practical and reproducible quantitative analysis. In this work, various CBI-amines were interrogated for their fluorescence characteristics over time under previously reported conditions (75:25 aqueous buffer:acetonitrile). An amine-specific decline in fluorescence and delay to reach maximum fluorescence were observed. Based on structural characteristics, we hypothesized that these effects were due to the solvents employed enabling analyte intermolecular interactions that resulted in fluorescence quenching over time. To mitigate fluorescence-quenching intermolecular interactions, we developed two strategies to improve the fluorescence of the CBI-product over long time periods: (1) the addition of the complexation reagent beta-cyclodextrin to the reaction matrix and (2) the substitution of acetonitrile with dimethyl sulfoxide. Both strategies improved fluorescence stability over time, and the incorporation of dimethyl sulfoxide also enabled more rapid attainment of maximum fluorescence and a higher absolute fluorescence when compared to initial conditions. When employed in combination, these two approaches further improve fluorescence stability over time for the most hydrophobic analytes. In the future, these strategies can be employed for the practical and reproducible quantitative analysis of primary amines in biological systems, including those related to neurological disorders and disease states
How does cross-sectional sampling bias our understanding of adolescent romantic relationships?: An agent-based simulation
No full textIntroduction: Adolescent romantic relationships are developmentally significant, but relatively brief and often disrupted by changes in context. Large individual differences and age-related change make sampling complex. Most adolescents have multiple romantic relationships. Which should we sample? To better understand the issues involved, this study used a simulation - an agent-based computational model - to generate model worlds, each following the relationships formed and dissolved over 5 years. Cross-sectional sample estimates of the number, duration, and type of relationships were compared to population parameters of all relationships formed within the 5 years. Computational models can provide useful insight into sampling bias because (1) the processes producing the results are explicit, (2) results can be replicated to reduce sample idiosyncrasies, and (3) sample statistics can be compared to known population parameters.
Methods: 1000 iterations were run of an agent-based model following 1000 individuals interacting for 60 months. The model included three types of individuals differing in relationship duration. Two sets of 1000 cross-sectional samples were drawn from the 60,000 cross-sectional months. Sample statistics were compared to the population parameters.
Results: Cross-sectional samples systematically over-represented longer relationships. The ability to detect individual differences in the duration and number of partners varied with time. These results suggest that cross-sectional survey and observational studies may be time sensitive and systematically distort our understanding of adolescent romantic relationships by oversampling longer-term relationships. Results also illustrate how computational models can provide insight into complex phenomena
The impact of lesbian bar ownership on USA lesbian bar geographies: all-gender/straight-integrated LGBTQ places by design
No full textOne longstanding explanation for the scarcity of lesbian bars in the United States is the lack of women\u27s ownership of durable spaces. This study interviewed 15 women owners of lesbian and LGBTQ bars to understand how they conceptualize the queer social spaces they control. Whether they owned a lesbian bar in a big city with a gayborhood or an \u27everybody\u27 gay bar serving a rural region, no owners prioritized women\u27s-only places, and all actively refused them. Many nevertheless reported practices to prioritize women in their spaces. Women\u27s ownership of LGBTQ spaces thus does not produce women\u27s-only spaces, even in self-described lesbian bars. These findings have three implications for our understandings of the spatial organization of lesbian and LGBTQ socializing. They shed light on the contested decline of women-only spaces, including the congruence between all-gender straight-integrated business philosophies and places that have survived the \u27great lesbian bar die-off\u27. They underscore the dramatic shift towards all-gender mixed LGBTQ spaces and the decline of gender-segregated socializing. Findings also raise the possible necessity for \u27time-space strategies\u27 of ephemeral placemaking practices even in erstwhile lesbian spaces due to the erasure faced by lesbians in straight-integrated spaces. Together, these findings underscore the necessary tension in lesbian geographies between a focus on durable places and ephemeral placemaking due to economic and spatial marginalization, time-space strategies that may increasingly be needed by all LGBTQ people in increasingly straight-integrated spaces
There\u27s the Black Woman Thing, and There\u27s the Age Thing : Professional Black Women on the Downsides of Black Don\u27t Crack and Strategies for Confronting Ageism at Work
No full textThis article problematizes the concept of Black Don\u27t Crack and challenges the universal desirability of youthfulness. This study is driven by two research questions: (1) How does the perceived youthfulness of professional Black workers shape their subjective experience of workplace interactions? and (2) What strategies do Black workers use to assert their expertise and legitimacy when confronted with prejudicial attitudes and interactions based on perceptions about their age? Drawing on 18 semi-structured interviews with professional Black women who are perceived as younger than they actually are, this article describes Black women\u27s experiences with ageism and their specific strategies for combating age bias in the workplace. The focus of this study diverges from most ageism studies focused on bias against older adults. Rather, this article contributes to our understanding of how gendered racism and ageism intersect when Black women\u27s chronological ages differ from how they are perceived
Have you heard the news? The effects of exposure to news about recent transgender legislation on transgender youth and young adults
No full textIntroduction: Over the last 3 years, there has been a proliferation of legislation aimed at restricting the rights of transgender Americans, including their access to gender-affirming health care. While the health implications of not having access to gender-affirming care are well documented, there may be additional indirect harms associated with proposing this type of legislation, such as those associated with being exposed to negative messages about transgender people or having to contend with friends and family who support the legislation.
Methods: This study was conducted between September and November 2021 and used a mixed-methods design to examine the implications of consuming news related to the recently proposed legislation as well as perceiving that people in one’s social network support such legislation on the health and well-being of transgender youth and young adults (n = 113).
Results: Results showed that news consumption was associated with increased rumination and physical health symptoms and that perceived support for the legislation was associated with greater rumination, depressive symptoms, physical health symptoms, and fear of disclosing one’s identity. Themes from the open-ended questions further underscored that the current legislation has impacted transgender youth and young adults’ access to general health care; increased experiences of discrimination and other maltreatment; and resulted in some respondents engaging in unhealthy coping responses.
Conclusions and Policy Implications: Policy makers should consider these adverse consequences when responding to current, and crafting future, legislation directed at transgender Americans
Sex, but not juvenile stress, affects reversal learning and DRL performance following cocaine administration
No full textIntroduction: Early adversity, impulsivity and sex all contribute to the risk of developing substance use disorder. Using rats, we examined how juvenile stress interacts with sex and cocaine to affect performance on a serial reversal task and a differential reinforcement of low rates 10 s (DRL10) task. The expression of dopamine-related proteins in several brain areas was also assessed.
Methods: From postnatal days (PND) 25–29, rats were exposed to a variable stress protocol. In adulthood, rats were trained on the reversal task and the effects of cocaine (0, 10, or 20 mg/kg, IP) on performance were assessed. Next, rats were trained on the DRL10 task and the effects of cocaine on performance were assessed. Finally, brains were extracted, and Western blot analyses conducted.
Results: Juvenile stress did not affect behavior. Sex did not affect baseline performance in either task. In the reversal task, cocaine decreased % high probability responses and the number of rewards earned in both sexes. Cocaine had sex-dependent effects on omissions, low probability responses and response latencies. In the DRL10 task, cocaine decreased the peak latency to respond and the number of rewards earned in both sexes. Cocaine had sex-dependent effects on peak rate of responding, response efficiency, burst responses and long responses. Female rats exhibited increased expression of DRD1 receptors in the striatum.
Discussion: These data contribute to the growing literature demonstrating sex differences in the behavioral effects of cocaine and suggest that DRD1 receptors could contribute to the observed behavioral sex differences
From Pirates to Patriots: Constructing the Oppositional Indian on the Road to the American Revolution
No full textReducing American Indian violence against colonizers to resistance is longstanding in the historiography of Indian-European encounter. This paper locates a formative juncture in the development of the Oppositional Indian trope in three acts of colonial rebellion on the eve of the American Revolution where spirited crowds of New England men defied British authority by storming ships, overpowering crews, and seizing cargos, all under the disguise of Indians. Rather than situating this maritime crowd action at the beginning of a revolutionary movement, as founding moments in a national narrative, this essay considers them as the aftermath of an older traumatic contest for Indigenous sovereignty and dominion
Introduction”: Comparative Approaches to Elena Ferrante: Traumas, Bodies, Languages
No full textThe introduction to this Special Issue lays out the rationale for analysing Elena Ferrante’s novels through a comparative perspective, in relation to works by Anglophone, French, and Italian authors. The editors first situate Ferrante’s writing within world literature, underlining the extensive intertextual network contained within and generated by her novels. Next, drawing on trauma studies, the introduction proposes trauma as a multidisciplinary interpretive lens for approaching Ferrante’s cultural production as a compelling site of traumatic expression. The introduction concludes by outlining the articles in the Special Issue with their specific theoretical and comparative frameworks, stressing their contributions to the larger conversations about world literature, women’s writing, and the global burgeoning of female literary genealogies
